A Combinatorial Strategy for Peripheral Nerve Repair Utilizing Photobiomodulation Therapy (PBMT) and 3D Printed Collagen Nerve Conduits- MHSRS 2024
Fellin c, steiner r, buchen j, woodle s, yuan x, anders j,
jariwala s
Abstract accepted for poster presentation at the 2024 Military Health System Research Symposium
The most severe case of peripheral nerve injury (PNI) involves complete transection of the nerve. One therapeutic approach uses nerve guidance conduits (NGCs) to facilitate nerve regeneration. Recently, three-dimensional (3D) bioprinting has been adopted for the fabrication of biomimetic conduits. However, many of these NGC therapies fail to achieve full reinnervation making it necessary to employ a combinatorial approach that incorporates treatments in conjunction with 3D printed conduits. Photobiomodulation Therapy (PBMT) utilizes electromagnetic energy to achieve beneficial therapeutic outcomes. Most notably, exposure to near-infrared light (700 - 1100 nm) has been shown to reduce inflammation and improve neural regeneration. Herein, we investigate whether the use of a novel 3D printed NGC in conjunction with PBMT (980 nm) will improve nerve regeneration when used as a combinatorial approach in a rodent sciatic nerve transection model.
The tissue of conduit-repaired rodents displayed no sign of foreign-body reaction, inflammation, or macrophage infiltration. The conduits remained sutured to the nerve stumps and displayed a high degree of ECM integration and neovascularization. Histological analysis indicates new nerve tissue present inside the conduit lumen with typical axon and vasculature anatomical features. Rodents treated with PBMT displayed significantly more regenerating nerve tissue within the conduit.
The results of this study demonstrate successful implantation of the DLP 3D printed NGC with no observable foreign-body reaction, a high degree of ECM integration, and neovascularization. Nerve regeneration was detected within the conduit and improved with the addition of PBMT. These findings support the use of PBMT as a combinatorial approach to conduit-based peripheral nerve repair.